ASMB,Q,C
*     NAME:   XABXY 
*     SOURCE: 92070-18219 
*     RELOC:  92070-1X219 
*     PGMR:   HLC 
* 
* 
*  **************************************************************** 
*  * (C) COPYRIGHT HEWLETT-PACKARD COMPANY 1979.  ALL RIGHTS      * 
*  * RESERVED.  NO PART OF THIS PROGRAM MAY BE PHOTOCOPIED,       * 
*  * REPRODUCED OR TRANSLATED TO ANOTHER PROGRAM LANGUAGE WITHOUT * 
*  * THE PRIOR WRITTEN CONSENT OF HEWLETT-PACKARD COMPANY.        * 
*  **************************************************************** 
* 
* 
      NAM XABXY,7  92070-1X219  REV.1941  790205
      ENT .XAX,.XAY,.XBX,.XBY 
* 
* 
      EXT .X.,.Y.,.A.,.B. 
* 
* 
A     EQU 0 
B     EQU 1 
* 
* 
.XAX  NOP           EXCHANGE A AND X
      STB .B. 
      LDB .X. 
      STA .X. 
      STB A 
      LDB .B. 
      JMP .XAX,I
* 
* 
.XBX  NOP           EXCHANGE B AND X
      STA .A. 
      LDA .X. 
      STB .X. 
      STA B 
      LDA .A. 
      JMP .XBX,I
* 
* 
.XAY  NOP           EXCHANGE A AND Y
      STB .B. 
      LDB .Y. 
      STA .Y. 
      STB A 
      LDB .B. 
      JMP .XAY,I
* 
* 
.XBY  NOP           EXCHANGE B AND Y
      STA .A. 
      LDA .Y. 
      STB .Y. 
      STA B 
      LDA .A. 
      JMP .XBY,I
* 
* 
* 
      END 
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